The Indiana
Department of Natural Resources’ Division of Entomology & Plant Pathology
has discovered that a shipment of boxwood plants infected with boxwood
blight was shipped to Indiana in May.

“This is important
because boxwood blight (Calonectria pseudonaviculata) is a fungal disease
that infests members of the popular Buxaceae family, and is often
transported through the nursery trade,” the DNR said in a statement released
this week. “Hosts include Buxus (boxwood), Pachysandra (Japanese spurge) and
Sarcococca (sweetbox).”

In total, 23 stores
in Indiana received infected material in early spring (particularly “Graham
Blandy” cultivar), and it’s possible that members of the public
inadvertently purchased some plants.

The fungus, which
can lay dormant in drier conditions, can be found on all above-ground
portions of the plant and presents itself as dark leaf spots. It causes
rapid defoliation, which typically starts on the bottom of the plant and
moves toward the top. This fungal pathogen can move through sporulation in
water and from dropped leaves. As a result, infection can spread to
surrounding plants from a single infected plant.

If you suspect one
of your plants shows signs and symptoms of boxwood blight, please call (866)
663-9684

For more
information on this pathogen, visit extension.purdue.edu/extmedia/BP/BP-203-W.pdf

A DNR inspector
found the plants at a national chain home and garden store in early October.
The shipment originated at a nursery in Oregon. It was also sent to stores
in 11 other states. Upon confirmation of boxwood blight on these plants by
the Purdue Plant and Pest Diagnostic Lab, the DNR required that the chain
remove all boxwood from their shelves for disposal and that the stores
mitigate the area through disinfection to ensure that the pathogen is no
longer present and able to infect further shipments of plants.

The DNR is
currently surveying for boxwood blight in Indiana. To date, the DNR has not
found the pathogen, except for a few interceptions like this one.